Switch mechanism



Dec. 6, 1927. R 16,810

E.B.THURSTON' SWITCH MECHANISM Original Filed July 1:5, 1921 s Sheets-She et 1.

Dec. 6, 1927. Re. 16,810

- E. B. THURSTON SWITCH MECHANISM Original Filed Julylb, 1921 3 Sheets-Sheet 2 /L 99 5 99 O v 99 /1 9 L 9 95 43 IO 7 4 A 34 36 q 7 33 96 106 L ms 67 60 Dec. 6, 1927.

E. B. THURSTON SWITCH MECHANISM Original Filed July 13 9 3 Sheets-Sheet 5 N guarantor Reissued Dec. 6,1927, 'zgguu'l'rao STATES s1 is.

wilhisinvention relates to electromagnetic motor operated switches. The invention has especial utility when-ineonporated in connection with polyphase pctrieenrrent torque or high internal re- Iggtan'ce switch-operating motors for elevator Mimi but is 'also useful in connection with electrical powerapparatus which is sub jected to frequent starting and stopping.

.Rcferring to the drawings: a t Figure 1 is awiring diagram wherein the alternating current is three-phase three-wire, incorporated for elevator service, with the controller on the elevator car, disclosing an embodiment of the invention; Fi 2: is a front-elevation of the switch boar for the wiring installation of Fig. 1;

3 is a detail view of a flexible couplmg for the motor shaft;

qyFig. 4 is aside elevation of one of the V accelerator switchesshowing the cam-shaft -Cmcross-section and the general relation of '7 t o threecams thereon; a

F'g. 5 is a detail view of the stop-carrying bracket for the weights;

Fig, 6 is a side elevation of the main h ntact-carrying .arm, the latter beiitlzpartly broken away;

gfihisa- Section of the rock shaft for maan or direction switch, showing the the arm for lifting the weights In the ,elevator shaft 1 having landings 2 1 isbperable ,elevator car 3 carried by hoist 40 line 4passin' about drum 5 over idler 6 to counterweigli' 7. Alternating electric current supply is shown which may be sixty 'yblathtee phase, by way of supply lines 8,, 9. ,10. From the line 8 branch line 11 ex.-

thence, by line 13 through lower overtravel switch 14, thence by line 15 through emerfswitch ltl in the car 3, thence byline through lower final or stopping switch olle'r21 in the car 3. r This contact motor switchbam, the cam-engaging means,

15' through upper overtravel switch 12.-

by way of line 19 to contact 20 on arn g 205.011 control1er21 when in off position 5am repeats acr ss to line 21 t ro gh upper,

PATENT OFFICE.

mmmstron, or TOLEDO, orno, ssIGNon TO THE HAUGHTON'ELEVATOR &

mcnmn 00., or TOLEDO, 01-110, A oonrona'monor o aro. 'swn'cn mncnanrsm.

i p, Originalv No. 1,585,517, dated May 18, 1926, Serial No. 484,429, filed July 13, 1921. Application for my reissue filed April'll, 1927. Serial No. 182,941. 1

final or stopping switch 22,-thence by line 23 to connect with the line 17. The emergency switch 16 is accordingl in the lines for both overtravel limitswit-c es as to the supplyfrom the line 8. From the supply line 10 is branch line 24 through upper overtravel switch 12, thence by way of, line 25 through the lowerovertravel switch 14, thenceby line 26 through the lower or final or stopping switch 18, and thence by way of line 27 to controller-carried bottom contact 28 on the controller 21. Should this lower final or stopping switch 18 be open. thereis branch line 29 from the line 26 by way of the upper stopping switch 22, extending from thence by line 30 to the lower contact 28 of the controller 21. Accordingly, in shifting the controller 21 to the left, the contact 20 is moved away from the line 21 and the contact 28 is moved away from the line 30. This automatically cuts out the upper final switch 22 as to the controller. 21, for this shifting of the controller to the left is effective for operating the car 3 for down ward travel. Reverse shifting for car travel upward cuts outtheswitch 18. i

The contact 20 is in this movement brought to connect the line 19 with line 32 extending to line 33. Simultaneously with this shifting of the contact 20 of the controller 21, the contact 28 of the co'ntroller'21'connects the line 27 with line 34 These lines 33, 34

extend to main switch operating motor 35.

' the third line to this motor being connected by way of line 36 to line 37, contact 38 on the accelerating switch, and thence by line 39 to line 40, connecting with the supply line 9. This main switch motor 35 has shaft 41, provided with flexible connection 42 to rockshaft 43 carrying cam 44 eifectivefor throwing switch contacts 45, 46 of the main switch.

It will be understood that the motor 35, as well as the other switch operating motors 51 and 73, shown in Figure 2, are of the type comprising a rotary magnet having a constant torque throughout its operating range, with a shaft having a limited rocking movement, and windings that permit the motor to stand still with the current on, for a considerable length of time, without becoming v overheated. v v

Further shifting of this controller 21 in the car to the left bring the contact 20 r .5 map? to line'47 extending toline 48, while simultaneou y ntaot28 is swung to line 54). These Oottz'nd to direction-switchoperating motor'51, having a third line 52 sgseire was stee wi h t e in 4 m t eeqcp iine' Tins energizing of direction switch torque motor 51 operates its motor shaft 53, having flexible coupling 54 with rock-shaft 55 carrying dm ection-mitch-operating cams 6, 57. The cam 56 for downdirection travel of the car 3 throws contacts 58, 59. The 69 is efiebti i e bj way oi line 60 from line h the main motor-switch contact Qt} to line 61,: Simultaneously-the shpply line 8 is eonnected-bycontact-58 with lind 'fifl. "T'lie' throw joithe main switch-con is connects-suppiy hnem with linefi3.

'iaese lilies area, as egrtend to three-phase slip fifiginain elevator motor 64. From the linefi2 extends'the' lirie to coil 66, thence by line 6'? to line 63. Accordingly, simultaneoii'slywith the energi ing of-the 'fieldeil from thelines 61, 62; 63 ofthls motor 64,

from connbcted'tolinhaf"The 'acc craterswitch tee-gee ii otof 73 on stream,- airing pinion; voigrsfesh'witli" en- 77! for ew -ta 'ee'gpe reenetiqp eriwng' -eemehea-rs,

" carrying cai'ns'79, 80,81?"-"}The travel 152 this mot v p ontroller 21 is shifted the 'ee e d pcsitioiigjthe direction-switch torquemotor "51 cam shaft 78 is resisted. "is riesistance'is helfeiifshdw hto who a" disk 82, having fiexible conn eotion 83w1th piston i'ncylinder 85 of a dash pottievicefthe -leakage fiectiv, ima 'ediatelj following the opemfienwf this dipcfion switch' motor 1 51" heeleratin" switchniotor' 73 is actuated.

A' tile-Shari ;8,*rem 1edrb the 'dash pot device 82; 83, 8%,85, star-ts operation there is a throwingcontact for cutting out'thfirst portion of startin lesistanlce 88 i the mainmotor' At '1;- e determined period of time thereafter in the "operation of the shaft 78, contact 89 cuts out an" add tional portion oi-the resisgance 88,a1,1d this is folwas aate' eeteet "38, therehj* e line initial elf fivcinentwf the contact 87 carries .in rni nener L0 is ca ried ingfthe' 'l ei 103 g D we e i ca tifi' main switch is thrown, the-contact 45 carries with it contact 91, thus maintaining closed the circuit between lines '37 and 40, so that the action of the accelerating switch es n t efiact an opening of h m i switch, The main motor 64; may accordingllyl be stopped by cuttin'g'out the direction switc oi moving controller 21 to neutral position to cut out the direction motor 51, and the main switch will stilhbehe-ld in.

.'However, any-other action of the'controller, or action as to the lines which cuts out the mainswitch, at once brings about a full stopping of the main motor 64, and there may not he a restarting of thismain motor 64'-'until after the accelerating switchfhas cometo startin position. For upward direction of trave the controller 21*is shifted to the right for'engaging contact 20" with oped for a main assembly control board e1nbodiment in the remote control of thesv'vitches from the elevator car. Control board 93, F igl 2, carries the usual v board contacts rigidly mounted thereon and supports br'ackets 95, .110, in which are'rotatably mounted the em shafts 43, 55,78 aridjlthe movable contact-carrying shafts T94; Mounted on the shafts 94 are arrns96, carrying movable contacts 45, 46, 5s, 59,*12r," 122,"e7," s9 and 90. ese movable contacts are normall ion lieldably directed towards-'their respective oard co 11facts by coild springsw, which are carried on bolts and normallylcoinpressed between the' arms 9'6 and nlits' on the ends of th bolts. The other ends ofthese bolts are anchored in switch-closing arnis 103, and the arrns '96 areapcrtured topermit of the passage of the bolts thereth'rough. Motorshaft 41 has arms 98 eta gered with arrns 99 on rhaft 43 "to carry tl ere between the flexible disk ,cou ling 42. Switch actuatg mm 4, ii nt on shaft has S mila actuating regions for each direction of oscilafii e onsi in o un icrm ac l t ng portions 100 and slow down portions. 101. 'lh' p tio s 100 of t a 4 appr ximate about ,5- i wa r iqn fr m; t e aeaen of contact of the roller 102 tobeacth ated" he wil t s permit i sah lt a. 1Qtck the am W th t moving the wilt hcl s- 0.12" .n amp a tw1 hths shat 84 efi tiye 1Y imu neou h owing Q contact areas ,96, a so fast on s a'ffiI94-. 103

ha extension 104 (Fig. '6), which in position of. rest of the cam 44 has its end104 registering with and adjacent to projection 1050f the cam. Cam 44 isv accordingly effective'ffor' holding the contact arms 96 "outward, so

open "until cam 44 rocked. p In rocking shaft 43 in either direction I? from the position of rest shown in Fig. 6, roller-.102 rides outward approximately 55 6 over an accelerating portion 100 and onto one o the slow down portions 101, effecting a throwing in of the contact arms 96 rapidly m at first and then more slowly as'they near i, 1 ,,contact-closi position. .As this throw is "3:1 being efiecte owing arm 103, the projection 104 moves N into one of the recesses 106, 107 of the "cam44. Integral with shaft-coupling arm 99 is a 11' depending arm 108, having enlarged offset :por'tion 109. The driven shaft section 43, adjacent the coupling 42, is mounted in bracket 110' which has bearing 111 (Fig. 5 for the time 94 and bearing 112 for the 1 2a shaft 43. Bracket 110 also carries below the bearing 112 an abutment or stop 113, wider :Loosely mounted upon the projecting por- I 1 tion of shaft 43 towards coupling 42 are t?! weights 114, 115, designed as rights and lefts.

Each weight has a sound deadening felt pad 1161 in .a depending ear 116 thereof for impacting with step 113, and weight 114 has a 1 similar pad 118 in-its upper portion for imwith projection 117 on weight 115. As he torque motor is energized to move in clockwise rotation, enlargement 109 on arm 108 moves into engagement with pad 116- of weight 114 and lifts weight 114 until the felt pad 118 seats against the projection 117. The extentof rocking of shaft 43 a is limited by weight 115 being held by the stop" 113 before it reaches dead center position. f This throw is adjusted to approximate" in either direction. When the movement of the shaft 43 is stopped by the Stop 113, the torque motor 35 will, of course. become stalled. The load of the weight upon the shaft 43 is greater-at starting and diss. iat s more nearly pverthe shaft 43. According 1y, this resisting means of the weight 114 or 115 grows less, while the resistance of the springs 97,91; the arms a proximately constant, but is not effective until there is contact and movement thereafter. Assoon as the motor 35 97 tend to return the g a mqfor and the'arms 103 toopen-switch osses, thusopening contacts 45, '46. This return to open-switch position is assisted by one ofthe weights 114, 115 rocking the shaft when 41, now not influenced by electromkgneticenergn'back'to its starting posi; fifin'fisidtermihed by the weights bringing that contacts 45, 46 are maintained by the travel of the switch} is than enlarged portion 109 of the arm 108.

, "miniehes as the center of gravity is brought 96 may remain apis deenergized the switch-opera-e the arm 108', 109 intoregistry with and clear of the stop 113, which stop receives the concussion impact of the weights.

The direction-switch motor-shaft section 53 is connected to cum shaft section 55 in a similar way as to coupling andweights, with arm, as the shaft section 41' is connected to the cam-shaft section 43 at the main switch motor 35,. Each of cams 56, 57 has the uniform accelerating region 100 (Figs. 8 and 9), approximating about 5 away from the tangent for the roller 102, which terminates in less active or slow-down portion 101. As to these portions. for action the cams 56. 57, are rights and lofts. However, the lock out portions to be engaged by the arms 104 are somewhat differently disposed. The cam .56 has stop portion 1.19extending in the same semi-circular region as its active cum portion, while the cam 57 has its'stop engaging portion 120 extending in the same semi-circular region as the active portion of this cam 57.

While in the operation of this device a one-direction-throw cam similar to 56 or57 might be used in connection with the mainsw-itch motor 35, such would thereby provea phase reversal stop device for the apparatus, precluding any throwing in of the switch motor 35 upon the reversal of phases. However, with the two-direction-throw cam 44 adapted to this main motor 35, there is an automatic provision caring for phase reverin that should supply lines 8, 9, 10, as installed, have the phases for operating the main switch 45 clockwise for Lip-direction travel of the elevator car 3, the rotation of the direction-switch .motor 51 also clockwise would result in throwing of they cam 57 for actuating the contacts 121, 122. On phase reversal and throwing of the" controller .21 in the same direction, motor35 would operate counterclockwise and-would also operate the direction-switch motor 51 counterclockwise, thereby throwing contacts 58, 59. This means'that the direction indication at the controller 21 in the car is correct even with phase reversal, because the reversal in the lines and one motor means a double re versal, thereby neutralizing the effect for car-travel-direction indication of the controller 21. It is true that with this reversal 7 51 being polyphase and of the torque type;

Furthermore, these, motors 35, 51, at once there is a failure on any phase, lose their torque and the springs 97 at once effective in conjunction with the weights 114, 115

in bringing the motors and likewise the switchcontacts into open or initial positions. A d n y, these m ter 3 51, because one phase is there is still a 1 I proper timing automatical y I cams 9-, 80,

the motor itself so carrying .energizingcurrent. when in thrown position, have this safety feature when but e phase line through each of the motors. rendering possible this control of polyphase switch-control devices remotely from the controller 21 in ,the car, the controller 21 is. connected to more than one hase of the supply lines. r

. e automatic operationfor self centering in off-position is also true as to the ac-v celerating motor 73, so pulled by the weight of dash-pot piston 84,. The three switchcontrolling lyphase motors 35 51, 73 may F return to off Eosition. This return by these motors too position may be on failure of one of theflphases of the supply, Such return occurs from a nonsealin position. As the accelerator motor 81 are bilateral, phase reversing motor 73 does not disturb the net result of the accelerating-switch control; these switch-operating motors is dissociated from the power motor line ascontrolled by its switches. These motors are in addition to the ower motor of the translation cirquit. urthermore, there is, due to this energizing action: of the rotating field in the torque motor, constant pull action by long as the energizing current is therein. 7

There is symmetry as to the actuators 35, 51, 7 3. There is symmetry as to the arms 96. Accordingly there is possible interchange of arms. and auxiliary motors, one of each capablo for replacement anywhere on the board. The design of the cams has developed a nquiet and. quick; control; operation by the remotecontrol herein 'disclosed.

. The extensions104 of the switchclosing arms 103 not only coact with stoprengagingf portions 119, 129o came 56,57- to prevent throwing in of the contaotrcarry-ing arms 96 before'their-respective cams are in posi- "tion to hold them out,- butsuchcxtensions' 104 are effective on rotation of the cams,

back to off position top'ositively withdraw the arms 96 from contact or thrown-in position withoutchattering or bouncing. Ao

cordingly, in any quick reversal of the switch-operatingmotor, there is an insured positive pullingout of the contact-carrying arms. The-throw of the arms 96 largely occurs as the rollers 102 ride'along the cam regions 100.'i The slowing up'of the travel of the roller 102' by riding upon-a cam portion 101 not only quiets" the final closing-in act-ionof meanness at the erging position ofthe con't'acts-iin the iiick' 't hfowin g in a s was. mess e 12; we

av l' of he r il low fl em tos mo e easily con: regs the 97 as the. period. t acheress as as ess disturbed and notwithstanding method of wiring,

Each of 0 beyond the contact-closingposition of the arms 96. There is accordingly a further compressionof the springs aft'ercontact closing for. holding the contacts against vibrationand for finally stalling the motor. This compressionof the springs also operates as a safety device, as" the springs 97 tend to return the arms 103 away from switchclosing'position, and is'of such effectiveness that even without the weights 114, 115 the arms may be quickly. released and Contact broken without detrimental arcing. 'While the wiring dia ram, Fig. 1, indi-.

cates the use of reversi le cam 44 for op' crating the main switch, one of the nonreverslble cams 56 or 57 could be used with equal advantage in connection with this tions for'th'e motor 35 are shown as nonreversible. If the reversible feature of cam 44 ,is-to be utilized, the motors 35 and 51 may be connected in parallel and both controlled through the wires 48 and 50. ires 33and 34; and the corres onding contacts in the car switch could t en be eliminated. The motor 73 is normally connected in parallel with the primary of the: power motor, so

that it automatically cuts out the accelerat ing resistance 88 y I The cams 7 9,180, 81 for operating the acoelerating switches areshown as having concentric portions on which the rollers 102 inasmuch as the connec roll after closing their respective switches,

and there is therefore little or nojtendency for the contact springs 97 to kick back or return the cam shaft to the neutralposition shown in Fig. 4. When operating a powerbreaking switch it is desirable, for safety reasons, that the springs 97 have an appreci able kick back action, to overcome any tendency of the switch to hold or stick in closed position. It is therefore desirable to give the slow-down portions 101 of the cams sulficient radius increase to at all times tend, through rollers 102, to return shafts 43 and 55 to their neutral positions.

The earns 44, 56 and 57 are so shaped thatthe initial and final movements of the contact-carrying arms 96 are gradual and the intermediate movements rapid, both in opening and closing ofthe switchcsnthereby rapidly increasing), the gap in contact opening and slowing down such movement just before neutral position is reached in opening and just before making contact in closing.-

Both the accelerating and slowing down movements of'the contact-carrying arms are gradual. so that there is no tendency to throw thev rollers 102 away fiom the cams,

and act aspositive lock-outs for the switches. Fee-sessile i s aft 55 we meted was J V i s tar-clockwise so that cam 56 would close its cooperating" switch, arm 104 01? the switch cooperating with cam '57 would remain "oppositethe concentric lock-out portion 120' on cam 57 and therebylock its switch out when itlie otherswitch is in its closed position.

,The terms closed-switch position 9switch"-clofsing position and contact-clos- OSition, asused in some of the claims, are intended to mean the closing of the contacts and do not include the follow up action of arms 03 in further. compressing the springs 971after contact closing,

The term switch3operating motor as used in some of the claims is intended to define a ,rotary magnet having a constant torque, with windingstha-t ermit the motor to stand for asubstantia period of time with, the power applied without injuryv to the windings.

' 'What I claim is I 1. Infa switch for power apparatus, a pair "of contacts one carried-by, a board and the other by a movable arm, a cam for shifting the arm, a switch-operating motor for actuating the cam, the cam being so shaped as to decrease the load on the motor as thecam in its travel brings the arm towards contact-closing position, and a spring so located that it increases the load on the motor after the contact is closed.

7 2. In a switch for power apparatus, a pair of contacts, an arm for closing the coni ,p tacts, a cam for shifting the arm, a'switch 1 i operating motor for actuating the cam, the cam being so shaped as to cause quick movement of the arm during the main portion of its travel towards contact-closing position and slow movement of the arm immediately previous to contact closing position, and a sfring so located as to increase the load on te motor after the contact is closed.

3. In a switch for power apparatus, apair of contacts, an arm for closing the contacts, a cam for shifting the arm. a switch-operate ing motor for actuating the cam, the cam being so shaped as to cause quick movement of the arm during the main portion of its travel towards contact-closing position andslow movement of the arm immediately previous to and following contact-closing position. and a spring so located as to increase the load on the motor after the" contact is closed.

4. In a switch for power apparatus, a pair of contacts, a'switch-closingarm, a switch motor adapted to actuate said arm fora "period of travel beyond the closing of the contacts, and intermediate transmission change-speed means between'the switch motor and arm forslowing-down action of the arm in the final movement thereof to closed position to quiet switch operation. 5. In a switch for power apparatus, a switch-closing arm, a switch-actuating motor adapted to actuate saidarm for a period of travel beyond the'clo'sing of the'contacts and to a stalled stop position ofthe motor with current still energizing the motor, and intermediate transmission changespeed means between the switch motor and arm.

including a slowing-down cam forefl'ecting contact closing to quiet switch operation.

. 6.. A switch for power apparatus, a switchclosing arm, a switch-actuating motor adaptedlto actuate said arm-for a period of travel beyond the closingof the contacts and to a stalled stop position .of the motor with current still energizing the motor, intermediate transmission change-speed means between the motor and arm including'a camfor slowing down actionofthe arm in contact closing to quiet switch'operation, and a-spring opposing motor driving during slowing down action of the cam after the contacts are closed.

7 Incombination, an electric switch having one of its contacts movable, a switchoperating motor, connections from the motor for operating the movable contact, yielding means operable after the contacts are closed to press them together and to oppose further rotation of the motor, and means other than said yielding means for stalling the motor when it hasi rotated alimited distrance after closing the contactsand "with current still energizing the motor, the 'said,

connectionsadapted to produce slowe'rqnove ment of the contact in proportion to the rotation of themotor as the contacts approach engagement. i

8. In combination, an electric switch having a switch-closing arm, a switch-operating motor, connections fromthe motor for-operating said arm, yielding means operable after the contacts are closed to press them i together and to oppose further rotation of the motor, and means other than said yield.- ing means for stalling the motor when it has rotated a limited distance after closing'the contacts and with current still energizing the motor, the said connections adapted to produce slower movement of the arm in proportion to therotation ofthe'motor'as the con-- tacts' approach engagement and thereafter until the motor is stalled.

9. In combination, anelectric switch having. a'movable contact, a switch-operating motor for moving the contact, yielding means pressing the contacts together and o posing further rotation of the motor aftert is contacts are closed, and means for returning the switch to neutral position, said means opposing the rotation of the motor prior to contact closing and gradually reducing such opposition subsequent to contact closing.

10. In combination, an electric switch comprising-a fixed contact, an arm mounted upon a fixed pivot, a contact on the arm in position to properly engage the fixed contact lac I an

a .between said v continued rotationoi the motor for a ,limitBd distance after the contacts are closed without changing the engagement of the confirst en 'a ged when the contacts are closed.

J f p, p a switch" for power apparatus, a" idoi' ahlehrm havi "a Contact, a second con;

a s itchspperatmg motor com risin "without inj y w t po pp i and peetio' 'sb'etween theinot'or and arm for 0105- thq'cdnftacts whenthe'motor isactu'ated,

sa d omedians comprising ai spring ada tedjtdield' after thecon'tacts are-closed and 'alldytf limited irritation. rm motor w thout l'mfiit mefi i heta g I fimbihati ialiielectricflswitch' comprising afar p'f dblitats one mounted upon ivote I sagag switch-operating motor wmdiings thatenable it to stall 'a di t plied," connections betiveen said motor and arm coniljn'ising a spring adapted to yield after the" contacts are c deed and al ow jtlfe power applied when 'opra'tioh is com leted;

Q, liihited rotation o i'the motor without move- 7 i'rint of the arm, and ine'ansother. than-said yielding means for stalling1 the motor with t e switch-closing 32KB combine ion, an electric switch com- I is I, and stan without inj for shifting a aii'of contacts; one mounted upon dmp sfi arm, a switchmperating motor windingsth at enable I it to stall ease ape adapted ay k fi ts and yielding'fmeans so located motor and contacts as to pert'at's' over the'same'e'xtent "at area that is 'tfitPto be engage the arm-contact, a

v p p the arm, a switch-operating ixfibtprjor actuating the cam independent of apparatus a spring co-acting for lowu action a or, said contacts are 'el o'sedfi'and means independent of 'the'f cam ;i'1itdthel springior opposing the rotation of motor as the-arm approaches contact- I closing position and adapted to stall the 'riiii tor with eurre'nt stillenergizin the same 7 a s the arm has reached the limit of its we ab contact-closing movement. a

1 4 111 combirmtio'n, an electricswitch having jpne [of contacts" movable, a switchoperlittifig A motor,f" cpnneetions from ,thta wr for oprating the movable con- I Q ifab fi after the contacts are elosed to priessgiiem together and 'to oppose rotation of the motor, "means inde-- pendent 5 t; the s ring f't stall the motor when iahasrotateq iii-lim ted. distance after clos i contacts and vwith current, still ergi ing helmetoi. said means tending to flset heresistanc'e' are s'pring to the iro- I of-tii ijrnotorasf't 'e motor approaches em g m II with power 'apthe arm to'close jsio.

' movable, contact-carrying arm, a cam ior -'controlling the movements of the arm, and a switch-operating motor for moving said cam, the cam being provided with aceelerating and slow-speed portions.

IBI A power-breaking switch provided with a movable switch-closing arm, a cam for controlling the movements of the arm, and a switch-operating motor for moving said cam, thercam being provided with acparts of said arm, an adjustable bolt eon mating the two parts oil-said arm, and a compression spring on said bolt for abutting one part of the arm and through the bolt efiective for urging the other part of the 7 ,arm towards said member, said two-part arm being operable for throwing the switch in response to movementsof the member.

18. A power-breaking switch provided with a movable arm and a cam for control- I ling" the movements of the arm, said cam -embodying'a lock-out portion effective for preventing accidental closing of the switch, and accelerating andslowin'g-down portions effective in turn to control the movements of the arm as the cam in its travel brings the arm toward fully thrown position;-

' 19. A power-breaking switch provided withi'a movable arm. and a rotary cam for controlling the movements of the arm, said cam embodying a first actuating portion of lessv than tangent from the starting point, and a second slowing'down portion effective in turn as the cam in its travel brings the arm to fully thrown pon'tion, and a third r lock-out portion for preventing accidental closing of the switch without rotating the cam. I I

20. A switch having a movable arm, a I motor having a shaft for shifting said arm to switch-closing position, and means preveluding operating said arm to switch-closmg fpositipn independently of operating said she t. a

21. A switch having a movable arm, a switch-operating motor having a shaft for shifting said arm to switch-closing position,

said motor having windings that permit it to 7 stand with power a plied without injuryto the motor, and 100 but means precluding nections between said shafts for commumiii? a a 24. A

eating movements from one to the other thereof, and means for positively holding the switch open until the motor shaft is moved in its switch-closing direction.

a 23. In combination, an electric switch having a movable contact, a constant-pull motor for operating said movable contact and adapted to close the switch-when the motor is actuated from open-switchposition to closed-switch position,v and means positively holding said contact 'in' its opentwitch position, when the, motor is in its open-switch position, a

I power-breaking switch provided Witha movable arm, a cam controllingathe movements of said arm, a switch-operating motor for moving said cam, the cam being provided with a portion cooperating with said a-rmto prevent accidental closing of the switch without rotating the motor, and un1- firmly accelerating and slow-speed portions successively cooperating with said arm as the cam is moved bythe motor for switch closin a v 1 253m combination, an electric switch having arnovable contact, a constant-pull motor for. operating said movable contact, and

if adapted to close the switch when the motor is actuated from open-switch. position to closed-switch position and to open the switch I, when actiiatedflfrom closed-switch position to, open-switch position, a cam controlling the speed of the movable contact from closedswitch to open-switch position to Cprevent bouncing, and means positively hol 1 when the motor isin its open-switch position.

26. In a switch for power apparatus, a switchoperating motor independent of said apparatus, a switch-closing arm, the motor Being adapted to actuate said arm for a period of travel beyond the closing of the switch and to a stalled position of the motor with current still energizing the same, a member directly connected to and positively driven by the motor, said member being movable relatively to said arm and having means coacting with said arm to move it ositively into and out of switch-closing position; v

. 27.. A switch having av movable arm, a motor having a shaft for shifting said am] to switch-closing position and capable of movement beyond switch-closing position, said motor comprising windings that enable it to stall and stand-without injury with the p applied, lock-out means precluding sit'ion, Without rotation of said shaft, and means forstalling the motor after it has passed switch-closing position. i

" 28. In combination, an electric switch, a

ing said shaft comprising windings that enng, said contact in its open-switch position operation of said arm to switch-closing poswitch-oporating shaft, a motor for operatable it to stall and stand without injury while energized, means for yieldingly closing the switch when the shaft is oscillated in one direction, means for positively opening the switch when the shaft 'is returned to its initial position, and means for stalling said motorafter it has moved a predetermined distance beyond switch-closing position.

'29-. A switch for, power apparatus, a switch-operating rnotor adapted to actuate a switch-closing arm for a period of travel beyond the closing of the contact, and intermediate transmission change-speed means between the motor and arm for slowing down action in contact closing for quieting switch operation, said transmission means being provided with a movable lock-out for the switch when in opened position.

30. In combination, an electric switch, a switch-operating shaft, a motor for operating said shaft comprising windings that enable it to stall and stand without injury while energized, means foryieldingly closing the switch when the shaft is oscillated in one direction, means for stalling said motor after it has moved a predetermined distance beyond switch-closing position, and means for positively opening the switch when the shaft is returned to its initial position and for-controlling the speed of such return so "as to avoid'bouncing of the switch arm.

31. A pairof switches for the translation circuit of a power motor apparatus, said switches each having a movable arm,ian actuating shaft for the switches,a switch-open ating motor in a control circuit complete in itself, said switch-operating motor beingfor actuating said shaft, and a cam for each switch mounted onsaid shaft, each cam provided With anarm-shifting portion and an arm lock-out portion oppositely disposed,

the cams. being so arranged on theshaft that rotation thereof in one direction throws one switch in and holds the other out and rotation in the opposite direction holds the one switch out and throws the other in.

32. In combination, an electric switch, a rock shaft, connections whereby rocking the shaft in one direction closes the switch, a stationary abutment beneath. the shaft, a weighted arm pivoted adjacent the abut- .ment and normally resting thereagainst, and

an actuating arm on the rock shaft, spaced from the weighted armwhen the rock shaft is at rest. in open-switch position and adapted to move against and then raise the weighted arm when the shaft is rocked to switch-closing position. i

33, In combination, an electric switch, a rock: shaft havinga normal rest position, connections whereby rocking the shaft from said position closes the switch, a weight having a normal rest position, and an arm on the shaft out of engagement with the weight when the parts are in'their rest position and adapted to move against and raise the weight when the shaft is rocked to switchclosing position.

34.- In combination, an electric switch rock shaft having a normal rest position, connections between the shaft and switch whereby the switch is closed by rocking the weights.

I an

' props shaft from? its rest position, a weighthaving a rest position, and lost motion' connections between the weight and shaft whereby the shaft ispermitted to move a short distance p from its rest'position without movingthe' weight and to, then raise, the weight upon the movement ofthe shaft further from its rest position. I I r 35. In combination, tw'oe'lectric switches.

a rock shaft having a position of rest. connections between the rock shaft and switches whereby both switches are, open when the shaft is in its position of rest and movement of the shaft in' one ire'ction clo's's one switch and movement of the shaft-Vin the other direction closes the other switch, an arm'pn ltheeshaft, a weight mechanism havinga' sition' of rest spaced from theposition rest of the arm, so that after the arm has traveiled alimited distance in either'direction' it engages and raises one of the 36. In combination, two electric switches, a rook shaft, connections between the rockshaft and switches fwherebv' rocking the shaft in one direction c lcises; one switch and mck'ifig the shaft, in the opposite direction c losesfthe other switchga' stationary" abutment beneath the shaft," two weights loosely pivoted upon theshaft and normaliyresting against the abutment, and arm'on theshaft ting downward when both switches are open and being narrowenthan the abut mentand inposition to engage a wei ht upon coming into alignment with either e 'ge? of theabutment. a v I, 37. A rock shaft having a driving section,

' a driven section aligned with said driving section, a flexible maintained transmission connection therebetween, a stationary, abutment adjacent the shaft, an fixed upon the driven sectio'n and registering with said abutment, spaced weights looselfy mounted on the driven section andnormallyhanging against said" abutment, said arm effective in one direction of shaft rotation to move into contact siniand then lift one 0 said weights imtifit contacts with the other weight while the latter rests against the ahutinent' and said armeifectivein the op:

osite direction of shiiftrotationto move into contact with and then; the other of said weights to bring it into contact with net of weighted: armson said driven section, one

of said arms adapted to he engaged by said. actuating arm and then lifted in one directio t'of shaft rotationand the other adapted to be engaged by said actuating arm: and then lifted in the other direction of shaft rotation, a pair ofswitches having patallel arms, and means onlthe shaft for throwing the arms of one switch in one direction of shaft-rotation and for throwing the arms of the other switch in the other direction of shaft rotation; 7 p

39. In a switch-operating mechanism,

driving and driven shaft sections having maintained transmission connectiontherebetwee'fi, a sw tch-Operating motor for actuating7 the driving shaft section, an actuating arm fixed on one of said shaft sections and a pair of weighted arms loosely mounted on one of said shaft sections, a stationary abutment adjacent the position of rest of said a'cactuatiiifi arm and said actuating arm being adaptedt'o engage and lift one ofsaid tion has a uniformly maintained driving.

tuating arm, said weighted arms normally 1 resting against said abutment clear of said connection, a momentum-storing weight loosely ro'ckably mounted on the shaft driven sectiomengaging means for angula'rly shift-- ing the weight on shaft actuation, and sound deadening stop means for the weight. w

41. Power actuation means for a switch including a rock-shaft driving section, a driven section with which said driving see tion has a uniformly maintained driving connection, a momentum-storing weight loosely" rockably mounted on one of said shaft sections, engaging means for angularlv 'shiftihg the weight on shaft actuation, and

sdiinddeadening stop means for the weight.

In testimony whereof, I have hereunto signed my nameto this specification.

" ERNEST B. THURSTON. 

